Fuel supply systems for internal combustion engines are well known and typically include means for maintaining a predetermined inline pressure of fuel being supplied to fuel injectors or carburetors or the like. A prior art fuel pressure regulator typically includes a valve having a matable seat and head. The valve seat includes a center-aligned fuel orifice. The fuel orifice is aligned with the centerline of the valve head, which causes the resulting opening and closing forces to be aligned on the same centerline, desirably providing a force balance to the regulator and intending to maintain a parallel orientation between the valve head and the seat. The valve head is generally pawn-shaped and includes a ball mounted on a stem and pivotably captured in a fixed retainer. Because the ball may swivel in the retainer, the valve head is undesirably responsive to flow cavitation turbulence occurring in the fuel orifice, resulting in valve vibration and audible noise (valve chatter). Because of this chaotic instability, the valve head sealing surface either can remain parallel to the valve seat sealing surface or can settle on the edge of the seat sealing surface at any one of an infinite number of angular positions. Because of minute pressure fluctuations on the sealing surface of the valve head, caused by cavitation, the valve head tends to flutter among ever-changing rest points on the seat. If the valve head does pivot and thereby remains in contact with the seat as flow rate is decreasing, the pressure at the set point flow rate will be significantly less than the actual increasing flow rate value (flow hysteresis). Audible noise and large hysteresis values can affect user satisfaction and also cause manufacturing problems and high reject rates.
What is needed is a fuel pressure regulator which is silent and lacks flow hysteresis.
It is a principal object of the present invention to provide an improved fuel pressure regulator wherein a valve head has a single and preferred mating position with a valve seat.
It is a further object of the invention to provide such a regulator which is simple and inexpensive to manufacture.
It is a still further object of the invention to reduce the manufacturing cost and waste for fuel pressure regulators.